What I am confused about is that after you plugged in those identities into the equation how did you end up with sin(x+π/6) = 1. Can you explain what you did to get that equation, because where did cos go.

What I am confused about is that after you plugged in those identities into the equation how did you end up with sin(x+π/6) = 1. Can you explain what you did to get that equation, because where did cos go.